Applied Physics A

, Volume 58, Issue 5, pp 513–518

Femtosecond-pulse laser ablation of human corneas

  • W. Kautek
  • S. Mitterer
  • J. Krüger
  • W. Husinsky
  • G. Grabner
Surfaces And Multilayers

DOI: 10.1007/BF00332446

Cite this article as:
Kautek, W., Mitterer, S., Krüger, J. et al. Appl. Phys. A (1994) 58: 513. doi:10.1007/BF00332446

Abstract

A femtosecond pulse laser in the visible spectral region shows promise as a potentially new powerful corneal sculpting tool. It combines the clinical and technical advantages of visible wavelengths with the high ablation quality observed with nanosecond-pulse excimer lasers at 193 nm. A femtosecond and a nanosecond dye laser with pulse durations of 300 fs and 7 ns, and centre wavelengths at 615 nm and 600 nm, respectively, both focused to an area of the order of 10−5 cm2, have been applied to human corneal ablation. Nanosecond laser pulses caused substantial tissue disruption within a 30–100 μm range from the excision edge at all fluences above the ablation threshold of Fth≈60 J cm−2 (Ith≈9 GW cm−2). Completely different excisions are produced by the femtosecond-pulse laser: high quality ablations of the Bowman membrane and the stroma tissue characterised by damage zones of less than 0.5 μm were observed at all fluences above ablation threshold of Fth≈1 J cm−2 or Ith≈3 TW cm−2 (3×1012 W cm−2). The transparent cornea material can be forced to absorb ultrashort pulses of extremely high intensity. The fs laser generates its own absorption by a multiphoton absorption process.

PACS

81.60 87.00 

Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • W. Kautek
    • 1
  • S. Mitterer
    • 2
  • J. Krüger
    • 1
  • W. Husinsky
    • 2
  • G. Grabner
    • 3
  1. 1.Laboratorium für Laser- und chemische DünnschichttechnologienBundesanstalt für Materialforschung und-prüfungBerlinGermany
  2. 2.Institut für Allgemeine PhysikTechnische Universität WienWienAustria
  3. 3.Augenabteilung der Landeskrankenanstalten SalzburgSalzburgAustria

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